Effects of viscosity on cerebral blood flow after cardiac arrest.

Objectives: To determine blood viscosity in adult comatose patients treated with mild therapeutic hypothermia after cardiac arrest and to assess the relation between blood viscosity, cerebral blood flow, and cerebral oxygen extraction.

Design: Observational study.

Setting: Tertiary care university hospital.

Fetal aortic distensibility, compliance and pulse pressure assessment during the second half of pregnancy.

The objective of the study was to measure fetal aortic pulse wave velocity and lumen diameter waveforms and subsequently calculate local distensibility, compliance and pulse pressure. A dedicated algorithm for optimizing lumen diameter assessment from radiofrequency ultrasound data is described. Biplane raw data were obtained from a matrix array transducer.

On-line blood viscosity monitoring in vivo with a central venous catheter, using electrical impedance technique.

Blood viscosity is an important determinant of microvascular hemodynamics and also reflects systemic inflammation. Viscosity of blood strongly depends on the shear rate and can be characterized by a two parameter power-law model. Other major determinants of blood viscosity are hematocrit, level of inflammatory proteins and temperature.

Estimating the effect of gestational age on test performance of combined first-trimester screening for Down syndrome: a preliminary study.

Objective: To establish how different methods of estimating gestational age (GA) affect reliability of first-trimester screening for Down syndrome.

Methods: Retrospective single-center study of 100 women with a viable singleton pregnancy, who had first-trimester screening. We calculated multiples of the median (MoM) for maternal-serum free beta human chorionic gonadotropin (free beta-hCG) and pregnancy associated plasma protein-A (PAPP-A), derived from either last menstrual period (LMP) or ultrasound-dating scans.

Jugular lymphatic sacs in the first trimester of pregnancy: the prevalence and the potential value in screening for chromosomal abnormalities.

Objective: To investigate the prevalence of detectable jugular lymphatic sacs in a setting for first trimester screening for Down syndrome, and to evaluate the influence of jugular lymphatic sacs on the screening performance for chromosomal abnormalities.

Methods: A prospective single center study (Erasmus University Medical Center, Rotterdam, The Netherlands) over a period of one year (January 2003-February 2004). First trimester nuchal translucency measurement was performed in a study population of 415 fetuses.

Application of the magnitude-squared coherence function between uterine and umbilical flow velocity waveforms for predicting placental dysfunction: a preliminary study.

To examine whether the magnitude-squared coherence between uterine and umbilical blood flow velocity waveforms can, in conjunction with estimated fetal weight, uterine and umbilical pulsatility indices, fetal and maternal heart rates, diastolic notching and the amniotic fluid index, create a sensitive and specific model for the prediction of placental dysfunction. Binary logistic prediction models are created for preeclampsia, pregnancy induced hypertension and intrauterine growth restriction in a study group of 284 unselected midtrimester pregnancies. In each study group, the median value of derived parameters were compared with the uncomplicated pregnancy control group.